You're incorrect
Sorry Sir but it is impossible to "fudge" a delivery. Dep. of Weights and Measures checks meters regularly to make sure that this thing doesn't happen. If you look at your ticket, the meter stamp will tell you exactly how many gallons were delivered.
In addition, if you really, really thought that they were stealing, I'm sure you would have contacted the proper authorities and filed a complaint. Instead I think you just like to bash people on this website.